Two-phase cooling of an electric machine
Hosseinpour, Nashmin (2024)
Diplomityö
2024
School of Energy Systems, Energiatekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2024080163215
https://urn.fi/URN:NBN:fi-fe2024080163215
Tiivistelmä
This thesis examines enhancement of heat transport in electric motors by implementing two-phase cooling with boiling in water jackets. The aim of study is to investigate the efficacy of boiling phenomena in increasing the thermal management of high-speed electric motors manufactured by The Switch company. Efficient heat dissipation is one of the most important factors to improve the performance and lifespan of electric motors, and boiling as a two-phase cooling method can help to achieve high heat transfer rates due to the latent heat of vaporization.
The study evaluated boiling phenomena and reviewed many advanced two-phase cooling techniques in electric motors such as heat pipes and rotating loop thermosyphons. Despite the numerous benefits of boiling heat transfer, there are also some challenges such as controlling large heat loads and potential efficiency reductions that can affect the heat transfer. In order to assess the feasibility and efficiency of incorporating boiling in water jackets for motor cooling, computational fluid dynamics (CFD) simulations using Ansys Fluent were utilized to model and examine the boiling process in a vertical pipe with upward flow. Eulerian multiphase method has been used and different parameters and submodels of boiling model were discussed. The results from the CFD simulations indicated that boiling technique might reduce the heat transfer amount based on the conditions each simulation. In addition, simplification of the motor circumstances was achieved by modeling a curved pipe. This revealed that boiling could not be the best option given the present motor settings, because the high vapor volume percentage acts as an insulator and prevents effective heat transfer. The run on the company’s motor model was not successful, and the reasons for this were investigated.
The study evaluated boiling phenomena and reviewed many advanced two-phase cooling techniques in electric motors such as heat pipes and rotating loop thermosyphons. Despite the numerous benefits of boiling heat transfer, there are also some challenges such as controlling large heat loads and potential efficiency reductions that can affect the heat transfer. In order to assess the feasibility and efficiency of incorporating boiling in water jackets for motor cooling, computational fluid dynamics (CFD) simulations using Ansys Fluent were utilized to model and examine the boiling process in a vertical pipe with upward flow. Eulerian multiphase method has been used and different parameters and submodels of boiling model were discussed. The results from the CFD simulations indicated that boiling technique might reduce the heat transfer amount based on the conditions each simulation. In addition, simplification of the motor circumstances was achieved by modeling a curved pipe. This revealed that boiling could not be the best option given the present motor settings, because the high vapor volume percentage acts as an insulator and prevents effective heat transfer. The run on the company’s motor model was not successful, and the reasons for this were investigated.